A proportionate mortality ratio analysis of pulp and paper mill workers in New Hampshire

A proportionate mortality ratio (PMR) analysis of 1071 deaths in pulp and paper mill workers in New Hampshire during 1975-85 showed an increase in cancers of the digestive tract and lymphopoietic tissues. A similar analysis of deaths for 452 timber cutters and loggers failed to show excess PMRs for cancers of these sites. Despite methodological constraints, these results suggest that one or more of the exposures experienced by pulp and paper mill workers may pose a significant carcinogenic risk. More definitive epidemiological studies are required to determine particular high risk processes or specific aetiological agents.     

Mortality among pulp and paper workers in Berlin, New Hampshire

Cause specific mortality was analysed among 883 white male workers from a paper company in Berlin, New Hampshire. Subjects were assigned to different exposure groups on the basis of their having worked in the pulp mill, the paper mill, or elsewhere in the paper company. A standardised mortality ratio (SMR) analysis was used to compare death rates for each of the exposure groups with United States national rates. For all the subjects, deaths due to all causes, all malignant neoplasms, and lung cancer were close to the number expected and excesses were noted for cancers of the digestive system and leukaemia. Among pulp mill workers, the number of cancers of the digestive system was raised and the SMR for pancreatic cancer was especially high (SMR = 305, 95% CI = 98-712). Among paper mill workers, more deaths were due to leukaemia and cancers of the digestive system than expected. These results are consistent with the findings from other studies that employment in pulp and paper mills is associated with excess mortality due to digestive and lymphopoietic cancers.     

Mortality among pulp and paper workers in Berlin, New Hampshire.

Cause specific mortality was analysed among 883 white male workers from a paper company in Berlin, New Hampshire. Subjects were assigned to different exposure groups on the basis of their having worked in the pulp mill, the paper mill, or elsewhere in the paper company. A standardised mortality ratio (SMR) analysis was used to compare death rates for each of the exposure groups with United States national rates. For all the subjects, deaths due to all causes, all malignant neoplasms, and lung cancer were close to the number expected and excesses were noted for cancers of the digestive system and leukaemia. Among pulp mill workers, the number of cancers of the digestive system was raised and the SMR for pancreatic cancer was especially high (SMR = 305, 95% CI = 98-712). Among paper mill workers, more deaths were due to leukaemia and cancers of the digestive system than expected. These results are consistent with the findings from other studies that employment in pulp and paper mills is associated with excess mortality due to digestive and lymphopoietic cancers.     

Mortality among production workers in pulp and paper mills

A cohort of 3,572 pulp and paper mill workers employed for at least one year between 1945 and 1955 was followed through 31 March 1977. Vital status was determined for 99% of the cohort. The 915 deaths observed were 79% of the number expected on the basis of comparable United States mortality rates. Statistically nonsignificant excesses of deaths due to lymphosarcoma and reticulosarcoma and to stomach cancer were observed. These findings tend to corroborate reports based on state vital statistics, and preliminary case-referent and population-based studies of workers in the pulp or paper industries. No deaths due to nasal cancer were observed, but only 0.6 were expected. When process-specific analyses were conducted, the excess risk of lymphosarcoma and reticulosarcoma was increased only for men who worked in sulfate mills. The excess risk of stomach cancer was limited to men who worked in sulfite mills. Process-specific standardized mortality ratios for these causes were highest after 20 years since first employment in the mills.     

Industry-wide study of mortality of pulp and paper mill workers

A study of pulp and paper mill workers indicated low risks of death from all causes (standardized mortality ratio (SMR) = 0.74) and all cancers (SMR = 0.81) compared with U.S. rates. The leukemia death rate in workers was not higher than the U.S. rate but was higher than the rate in county populations surrounding mills. Workers whose last jobs were in the finishing areas of the mills had an elevated SMR for liver cancer. An internal comparison of occupational characteristics indicated that workers employed in mills using other chemical pulping operations had significantly elevated mortality from all causes, all cancers, heart disease, lymphomas, and brain cancers. Lung cancer mortality was elevated in mills using kraft pulping. The internal comparisons confirmed the association between work in finishing and the risk of liver cancer. This study was designed to investigate whether pulp and paper mill workers have any risks that would indicate the need for studies detailing exposures. Am. J. Ind. Med. 33:354–365, 1998. © 1998 Wiley-Liss, Inc.     

Gliomas among men employed in the Swedish pulp and paper industry

OBJECTIVES: This study investigated whether previous findings of an increased risk of gliomas among workers in some pulp and paper mills could be confirmed for all Swedish pulp and paper mill workers and whether the increase could be attributed to certain occupational groups. METHODS: The study was based on the Swedish Cancer Environment Register, which links the incidence of cancer from 1971 to 1990 and the 1960 and 1970 census data on codes of occupation and industry for the whole population. Standardized incidence ratios (SIR) were used to estimate the risks for men in different occupations in pulp (N = 28,142) and paper (N = 39,169) mills in 1960, 1970 or both years as compared with those of all gainfully employed men in Sweden. RESULTS: Maintenance workers employed in pulp or paper mills in 1960, 1970 or both years, as well aspulp workers, showed an increased incidence of gliomas in 1971-1990 [SIR 1.5, 95% confidence interval (95% CI) 1.1-2.1 and SIR 1.5,95% CI 1.0-2.2, respectively], whereas the incidence among process workers in paper mills was lower than expected (SIR 0.6, 95% CI 0.3-0.9). Taken together, all employed men in the pulp mill industry had an increased incidence of gliomas (SIR 1.3, 95% CI 1.0-1.7). CONCLUSIONS: Pulp mill workers, but not paper mill workers, were found to have more gliomas in 1971-1990 than expected. There was an increased risk of gliomas among maintenance workers in both pulp and paper mills. Few risk factors for brain tumors are recognized, and the causes of the increase are not obvious.     

Health effects of working in pulp and paper mills: Malignant diseases

This paper reviews the available literature regarding the work environment in pulp and paper mills and the risk for malignant diseases. An increased risk for lung cancer among pulp and paper mill workers has been reported. Most studies are inconclusive with regard to considerations of etiologic agents. However, maintenance workers seem to be at an increased risk for lung cancer, as well as for malignant mesothelioma, indicating that this occupational group was (is) exposed to asbestos. Workers exposed to chlorine compounds also seem to run an increased risk for lung cancer. An increased risk for malignant lymphomas among pulp mill workers is a constant finding. The increased risk is observed both among sulfite and sulfate workers, indicating a common exposure. Such an exposure could be wood dust, terpenes, or preservatives present in the wood. An increased risk for leukemias has been found in many studies carried out on pulp and paper workers, but the studies do not permit any conclusions about etiologic factors. In some studies an increased risk for stomach cancer has been found. However, the socioeconomic status of the workers is strongly related to stomach cancer, and factors, such as dietary habits, have not been taken into account in any of the reviewed studies. Hence, no further conclusions can be drawn regarding etiologic agents. © 1996 Wiley-Liss, Inc.     

Cohort study on cancer mortality among workers in the pulp and paper industry in Catalonia,Spain

We examined mortality in a retrospective follow-up study of 3,241 workers employed between 1970–1992, in four pulp and paper mills in Catalonia, Spain. Vital status was determined for 95% of the cohort. Exposure was reconstructed using job histories and a company exposure questionnaire. Standardized mortality ratios (SMR) were derived using mortality rates of Spain as the reference. For all workers, mortality from all causes (SMR = 76; 95%; confidence intervals [CI] = 65–88; 189 deaths) and all malignant neoplasms (SMR = 93; CI = 72–119; 65 deaths) were less than the expected. Excess risk was observed for mortality from all neoplasms in females (SMR = 168; CI 84–303; 11 deaths), for large intestine cancer in both sexes (SMR = 250; CI = 115–525; 8 deaths), particularly after 10 years of employment and latency (SMR = 355; CI = 154–701; 8 deaths), and for breast cancer in females (SMR = 286; CI = 77–732; 4 deaths). These findings suggest that workers employed in the pulp and paper industry may have an excess risk of specific cancers. © 1996 Wiley-Liss, Inc.     

Testicular cancer among Swedish pulp and paper workers

BACKGROUND: The incidence of testicular cancer has increased in recent decades. The aims of the present study were to elucidate whether Swedish paper and pulp mill workers had an increased incidence of testicular cancer, and to investigate whether certain occupational groups within the pulp and paper mill workforce were at increased risk. METHODS: The study was based on the Swedish Cancer Environment Register, which links the incidence of cancer for the period 1971-1990 with 1960 and 1970 National Census data on specific industries and occupations for all employed subjects in Sweden. RESULTS: Among maintenance workers employed both in 1960 and in 1970 in paper mills there was an increased risk for testicular cancer (standardized incidence ratio (SIR) 7.4, 95% confidence intervals (CI) 1.5-22), especially for seminomas (SIR 10.1, 95% CI 2.1-29). Maintenance workers were also at increased risk when analyzing workers employed in 1960, 1970, or both years. CONCLUSIONS: This study indicates an increased risk for testicular cancer, especially seminomas, among maintenance workers, but not among process workers, in Swedish paper mills.     

Mortality pattern among pulp and paper mill workers in Sweden: a case-referent study.

The mortality pattern among Swedish pulp and paper mill workers was evaluated in a case-referent study encompassing 4,070 men decreased during the period 1950-1987. The subjects were identified from the register of deaths and burials in six parishes. A significantly increased mortality was seen for diabetes mellitus and for secondary tumors of the lung and liver among the pulp and paper mill workers. Indications of excess risks were also found for obstructive lung disorders, pulmonary emboli, accidents, and pneumonia, as well as for malignant lymphomas, leukemias, and cancer of the pancreas and stomach. In the only parish where a sulfite process was exclusively used, cancer of the digestive tract and especially of the rectum was found to be in excess. Except for this parish, the sulfate process predominated in the plants included. The mortality pattern found in this study is in reasonable agreement with findings in various studies from this type of industry.     

Cohort cancer incidence among pulp and paper mill workers in British Columbia.

OBJECTIVES: A study was conducted to investigate cancer risks in a cohort of pulp and paper workers. METHODS: All male workers with > or =1 years of employment in 14 pulp and paper mills in 1950-1992 were studied. Standardized incidence ratios (SIR) were used to compare the cancer incidence of the cohort with that of the Canadian male population. Record linkage with the National Cancer Registry was performed using the generalized iterative record linkage method. RESULTS: Altogether 1756 cancer cases were observed in the entire cohort. For > or =15 years of work, the entire cohort had significantly increased SIR values for pleural and prostate cancer and skin melanoma; there was also a significantly increased risk for skin melanoma among workers in the kraft process only, rectal cancer among workers in the sulfite process only, and stomach and prostate cancer and all leukemias combined among workers in both the kraft and sulfite processes. A separate analysis comparing workers in pulping and papermaking with those in the pulping process only did not reveal any difference in cancer risk and hence did not modify the results. The SIR values for skin melanoma were not significantly increased in a comparison using the British Columbia male population. Nine of 10 pleural cancers were mesotheliomas, which likely reflect past asbestos exposure. CONCLUSIONS: The results suggest that long-term work in the pulp and paper industry is associated with excess risks of prostate and stomach cancers and all leukemias for work in both kraft and sulfite processes and of rectal cancer for work in the sulfite process only.     

Mortality among Workers Exposed to Carbon Disulfide

Mortality experience was investigated at a plant in Ontario that produced viscose rayon, with carbon disulfide as a main raw material. Work-history records for 279 deceased workers at the plant (plant A) were obtained and compared with those for 511 deceased workers at a pulp and paper plant in the same city (plant B). In a proportional mortality analysis, using as a reference the general population of Ontario, at both plants there were fewer deaths from ischemic heart disease than expected (the proportional mortality ratios [PMRs] were 83 at plant A and 95 at plant B) but more deaths than expected from cerebrovascular disease (PMRs were 115 at plant A and 149 at plant B). In a subgroup of plant A workers who had been employed in high-carbon-disulfide exposure areas, deaths from ischemic heart disease were less than expected (PMR = 82), particularly among those who worked in these areas for more than 5 y. Most deaths occurred among those aged 65 y or more. Mortality from strokes, however, was greater than expected (PMR = 207, p < .05); the excess was confined to workers who died at age 65 y or older (PMR = 229, p = .01). Proportional mortality from strokes was also increased in the pulp workers among those who died at age 65 y or older (PMR = 153). In a case-control analysis, the risk of ischemic heart disease at plant A was slightly less than at plant B (odds ratio [OR] = 0.92, 95% confidence interval [CI] = 0.60–1.42), with no association between risk and years worked in high-carbon-disulfide areas (OR/y = 0.99, 95% CI = 0.94–1.03). Among those who died at age 65 y or older, the risk of stroke in the high-exposure subgroup was (a) increased significantly, compared with other plant A workers (OR = 4.92, 95% CI = 1.66–14.65); and (b) increased slightly, compared with plant B workers (OR = 1.37, 95% CI = 0.83–2.26). These results suggested an unusually low risk of strokes among other plant A workers. The risk of stroke was associated with years in high-carbon-disulfide areas (OR/y = 1.03,95% CI = 0.96–1.10). The observed increase in proportional mortality from strokes may represent a chance finding, but a causal role for exposure cannot be excluded.     

Lung cancer mortality in a cohort of older pulp and paper workers

The occurrence of deaths due to lung cancer was studied among 883 white male workers from a pulp and paper company in northern New Hampshire. All subjects had participated in a longitudinal study of respiratory morbidity, and data from interviews were used to construct lifetime cigarette smoking and occupational histories. Most of the subjects had entered follow-up in the 1960s and, at that time, their mean age was 51 years and they had worked for the pulp and paper company a mean of 25 years. By the end of follow-up in 1992, the 512 deceased subjects included 35 whose underlying cause of death had been lung cancer. With an internal comparison using the Cox proportional-hazards model, the hazard ratio for sulfite pulp mill work was 2.5 (95% CI 1.3-4.9), while controlling for the effects of age, cigarette smoking, and work in other parts of the pulping operation. In addition, the hazard ratio for the combination of >35 pack-years of smoking and >10 years sulfite mill work was greater than the product of the hazard ratios for each factor alone. While these findings are consistent with past asbestos exposure in the sulfite pulp mill environment, the absence of mesothelioma cases is inconsistent with this type of exposure.     

Exposure to asbestos and lung and pleural cancer mortality among pulp and paper industry workers

We studied the mortality from lung and pleural cancers in a cohort of 62,937 male workers employed for at least 1 year in the pulp and paper industry in 13 countries during 1945 to 1996. Mill departments were classified according to probability and level of exposure to asbestos on the basis of available dust measurements and mill-specific information on exposure circumstances. Thirty-six percent of workers were classified as ever exposed to asbestos. Standardized mortality ratios of lung cancer were 0.99 (95% confidence interval [CI], 0.90 to 1.08) among unexposed and 1.00 (95% CI, 0.90 to 1.11) among ever exposed workers. The number of pleural cancer deaths among unexposed workers was 10; that among exposed workers was 14, most of which occurred among maintenance workers. In internal analyses, a trend in mortality from either neoplasm was suggested for estimated cumulative exposure to asbestos, weighted for the individual probability of exposure within the department and for duration of exposure (relative risk for lung cancer for 0.78+ f/cc-years, as compared with < or = 0.01 f/cc-years: 1.44; 95% CI, 0.85 to 2.45; corresponding relative risk for pleural cancer: 2.43; 95% CI, 0.43 to 13.63). Despite a possible nondifferential misclassification of exposure and outcome, this study suggests that the carcinogenic effect of asbestos can be detected among workers employed in industries such as the pulp and paper industry, in which it is not considered to be a major hazard.     

Lung Cancer Mortality in a Cohort of Older Pulp and Paper Workers

Abstract

The occurrence of deaths due to lung cancer was studied among 883 white male workers from a pulp and paper company in northern New Hampshire. All subjects had participated in a longitudinal study of respiratory morbidity, and data from interviews were used to construct lifetime cigarette smoking and occupational histories. Most of the subjects had entered follow-up in the 1960s and, at that time, their mean age was 51 years and they had worked for the pulp and paper company a mean of 25 years. By the end of follow-up in 1992, the 512 deceased subjects included 35 whose underlying cause of death had been lung cancer. With an internal comparison, using the Cox proportional-hazards model, the hazard ratio for sulfite pulp mill work was 2.5 (95% CI 1.3–4.9), while controlling for the effects of age, cigarette smoking, and work in other parts of the pulping operation. In addition, the hazard ratio for the combination of > 35 pack-years of smoking and > 10 years sulfite mill work was greater than the product of the hazard ratios for each factor alone. While these findings are consistent with past asbestos exposure in the sulfite pulp mill environment, the absence of mesothelioma cases is inconsistent with this type of exposure.     

Mortality from asthma and chronic obstructive pulmonary disease among workers in a soft paper mill: a case-referent study.

In a case-referent study encompassing 33 cases and 228 referents the potential risk for asthma and chronic obstructive pulmonary disease and respiratory cancer among workers in a soft paper mill was evaluated. The cases were selected from registers of deaths and burials in the parishes around the paper mill. Information on exposure was obtained from the personnel register of the mill but because of shortage of information the cases could only be classified as "exposed" or "non-exposed." At some places in the mill the concentrations of paper dust had previously been high, 10-30 mg/m3. Employment at the paper mill was found to be associated with an increased risk of bronchial asthma and chronic obstructive pulmonary disease (odds ratio = 3.8, p less than 0.05).     

Deaths from primary brain cancers, lymphatic and haematopoietic cancers in agricultural workers in the Republic of Ireland.

STUDY OBJECTIVE--To ascertain if agricultural workers in the Republic of Ireland had a higher than expected mortality from brain and haematopoietic cancers than occurred in the general population. DESIGN--The Central Statistics Office of Ireland provided computer analysis of all deaths coded as cancer of the brain, ICD 191, and of lymphatic and haematopoietic cancers, ICD codes 200-208, by socioeconomic, sex, and age groups, from 1971 to 1987. The deaths were then analysed by socioeconomic group and compared with the expected number of deaths in the general population. SETTING--A cluster of four deaths from primary brain cancer, three from leukaemia, and one from Hodgkin''s disease, occurred in the research and technical staff of the former Agricultural Institute of the Republic of Ireland in men under the age of 65. This raised the question, were farmers more likely to get these forms of cancer due to exposure to herbicides or fertilisers? SUBJECTS--All deaths in the Republic of Ireland from 1971 to 1987 by socioeconomic group. MAIN RESULTS--Although deaths reported as due to primary brain cancers had increased in all socioeconomic groups in the two time periods studied, there was no greater increase in farmers and a smaller increase in other agricultural workers and fishermen. Deaths from Hodgkin''s disease and multiple myeloma, and to a smaller extent from leukaemia, had also increased. The increase in reported mortality of these haematopoietic cancers in farmers was no greater and in other agricultural workers it was less than in the general population. CONCLUSION--There was no evidence that farmers had any greater increase in mortality from these cancers than the general population. The cluster of brain and haematopoietic cancers in research and technical staff at the Agricultural Institute of the Republic of Ireland does not reflect a high risk of these cancers among the general farming population, but strongly supports the need for a compilation of a register of causes of death of laboratory workers in a number of countries.     

Asbestos disease in sheet metal workers: proportional mortality update

This paper, updating the findings of an earlier study, provides additional evidence that sheet metal workers in the construction trades are at increased risk for asbestos-related disease. A proportional analysis of cause of death among 331 New York sheet metal workers found a significantly elevated PMR for lung cancer (PMR = 186). In addition, there were six deaths attributable to mesothelioma (three classified as lung cancer deaths) and three death certificates mentioned asbestosis or pulmonary fibrosis, although none of these three deaths were attributed to these diseases.     

广西某蔗渣制浆造纸厂职业卫生现状调查与评价

目的为了解广西某甘蔗渣制浆造纸厂作业场所职业卫生现状以及对作业工人健康的影响情况,并作出评价为同类型的蔗渣制浆造纸厂的职业卫生防护作出参考。方法对广西某蔗渣造纸厂进行职业卫生现状调查、职业病危害因素检测及评价。结果该厂未设车间浴室,个人防护用品、应急救援及职业健康检查不完善;职业病危害因素检测中,2个工种接触的粉尘浓度超标,2个工种接触的氯气浓度超标,9个工种接触的噪声超标,5个工种接触的高温均超标。结论应根据蔗渣造纸厂的生产特点进行职业病危害预防与控制,完善所采取的职业病危害防护措施,以更好地保护作业工人的健康。     

The third analysis of cancer mortality among Japanese nuclear workers, 1991-2002: estimation of excess relative risk per radiation dose

The present study estimated excess relative risk per sievert (ERR/Sv) of cancer mortality among the cohort of 200?583 male Japanese nuclear workers, with an average individual cumulative dose of 12.2 mSv (<10 mSv, 75.4%; 100 + mSv, 2.6%), conducting Poisson regression using dose category specific observed and expected numbers of deaths, and average doses obtained from the official report of the Radiation Effects Association (REA) on the analysis of mortality of Japanese nuclear industry workers for 1991-2002, which reported the estimates of ERR/Sv for leukaemia but not for all cancers or any other cancer site. The possible confounding biases from drinking alcohol and smoking tobacco were evaluated by examining the association of cumulative radiation dose with the mortality of cancers related to drinking or smoking. For leukaemia (80 deaths), the estimate of ERR/Sv was - 1.93 (95% confidence interval (CI) = - 6.12, 8.57). For all cancers excluding leukaemia (2636 deaths), while the ERR/Sv was estimated to be 1.26 (95%CI = - 0.27, 3.00), confounding by alcohol consumption was suspected since the ERR/Sv estimate of alcohol-related cancers was 4.64 (95%CI = 1.13, 8.91) and the ERR/Sv estimate of all cancers excluding leukaemia and alcohol-related cancers was 0.20 (95%CI = - 1.42, 2.09). In conclusion, confounding by important lifestyle factors related to cancer risk may have a substantial effect on risk estimates, especially when conducting studies of low cumulative dose and, accordingly, low statistical power. Pooled analysis or meta-analysis of nuclear workers for solid cancers needs to take this point into account.